多晶黑硅表面微结构对电池效率的影响

采用Ag离子辅助化学刻蚀法制备了多晶黑硅薄片,使用NaOH溶液处理多晶黑硅表面,增大其表面纳米孔直径,使SiNx薄膜能够均匀覆盖整个黑硅表面,提高黑硅的钝化效果,进而提高多晶黑硅电池光电转化效率.通过反射谱仪、扫描电子显微镜(SEM)、太阳电池测试系统等测试和表征不同扩孔时间对多晶黑硅各方面性能的影响.结果表明:未被NaOH扩孔处理的多晶黑硅的反射率最低,为5.03％,多晶黑硅太阳电池的光电转化效率为16.51％.当多晶黑硅被NaOH腐蚀40 s时,反射率为10.01％,电池的效率为18.00％,比普通多晶硅太阳电池的效率高2.19％,比未被扩孔处理的多晶黑硅太阳电池的效率高1.49％.

Effect of Multi-Crystalline Black Silicon Microstructure on the Efficiency of Solar Cells

The multi-crystalline black silicon wafers were fabricated by Ag-assisted etching.NaOH solution was used to increase the diameter of nanocrytalline pore on the black multi-crystalline silicon surface,which makes the silicon nitride (SiNx) layer deposite the whole black silicon surface uniformly,improves the passivation effect of black silicon,and then improves the photoelectric conversion efficiency of black multi-crystalline silicon cells.The performance of the multi-crystalline black silicon were investigated by reflection spectroscopy,scanning electron microscopy (SEM) and solar cell test systems with different etching time.The qualitative analyses indicate that the multi-crystalline black silicon wafers without NaOH treatment show the lowest reflectivity of 5.03％,and the photoelectric conversion efficiency is 16.51％;after etched by NaOH solution for 40 s,the reflectivity and the efficiency of the black silicon are 10.01％ and 18.00％,respectively.Compared with those of the normal multi-crystalline solar cell and multi-crystalline black silicon without pore-widen process,the photoelectric conversion efficiency increases 2.19％ and 1.49％,respectively.